ROCHESTER — Democratic presidential candidate Hillary Clinton told more than 2,000 New York schoolteachers Friday night that GOP candidates Donald Trump and Ted Cruz were out to “slash and burn” the country’s public education system, while billing herself as a “partner” who would increase teacher pay and improve technology in aging schools.

“We have a political fight on our hands,” Clinton said in a nearly hourlong address to the New York State United Teachers annual convention in Rochester. “There’s no doubt in my mind any of the Republicans would be a disaster for public education.”

The speech before the state’s largest labor union, with some 600,000 members, was the last of four campaign events Clinton headlined Friday in Buffalo and Rochester.

Clinton, who has been sprinting between New York City and upstate ahead of the state’s April 19 primary, is trying to block rival U.S. Sen. Bernie Sanders of Vermont from adding New York, the state where she served as senator for eight years, to his recent string of primary victories.

But Clinton did not mention Sanders in her address, instead focusing her attacks on Trump and Cruz.

She condemned Cruz for his calls to “abolish” the U.S. Department of Education. Cruz has said local governments should be in charge of setting curriculum standards, and has argued for smaller government. Trump in April also said he believes the department should be “largely eliminated.”

“I want every teacher, principal, parent and student to know you will have a partner in the White House,” Clinton said to an audience where hundreds wore blue shirts that read “we need a president who will fight for strong public schools.”

Clinton also pressed the issue of education to prepare students to compete globally, at a rally in Buffalo that drew more than 2,000 supporters, and a rally in Rochester that drew an overflow crowd of more than 3,000.

She touted her plans to create jobs by increasing federal investment in research programs across all fields of science.

“We cannot lose the American advantage in research we use to dominate in the world,” Clinton told a crowd at the Pierce-Arrow Museum in Buffalo.

She was introduced by Lt. Gov. Kathy Hochul, who said Clinton shouldn’t worry about her support among Buffalo Democrats, “because we’ve got your back.”

At a more intimate round-table discussion at the Jacobs Institute of Buffalo Niagara Medical Campus, Clinton told an audience of about 20 doctors and researchers, that if elected she would “have a much heftier research agenda.” She touted her work as a senator to secure $10 million in federal funding for the medical facility that employs some 10,000 people.